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April 13 (Reuters) - A highly contagious variant of COVID-19 first identified in Britain does not cause more severe disease in hospitalised patients, according to a new study published in the medical journal The Lancet Infectious Diseases on Monday.

The strain, known as B.1.1.7, was identified in Britain late last year and has become the most common strain in the United States, according to the United States Centers for Disease Control and Prevention.

The study analysed a group of 496 COVID-19 patients who were admitted to British hospitals in November and December last year, comparing outcomes in patients infected with B.1.1.7 or other variants. The researchers found no difference in risks of severe disease, death, or other clinical outcomes in patients with B.1.1.7 and other variants.

"Our data, within the context and limitations of a real-world study, provide initial reassurance that severity in hospitalised patients with B.1.1.7 is not markedly different from severity in those without," the researchers said in the study.

A separate study published in The Lancet Public Health medical journal found that vaccines were likely to be effective against the British variant since there was no apparent increase in reinfection rate when compared to non-UK variants.

According to British scientists, the British variant was about 40%-70% more transmissible than previously dominant variants.

The studies also confirmed the previous findings that B.1.1.7 was more transmissible.

(Reporting by Ann Maria Shibu and Maria Ponnezhath in Bengaluru; Editing by Chris Reese and Stephen Coates)